9 squared is 81
81=9^2
Or, (3^2)^2. Double square!
Answer:
1. a) 8 cm × 8 cm = 64 sq cm
b) (64 cm²) × 6 squares = 384 sq cm
2. 152 sq cm
Step-by-step explanation:
1. The area of any rectangle is the product of its length and width. For a square, length and width are the same. The square faces of your die have length and width of 8 cm, so the area is (8 cm) × (8 cm) = 64 sq cm.
A cube has 6 faces of identical size, so the total surface area is 6 times the area of one face. Your cube's surface area is 6 × 64 sq cm = 384 sq cm.
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2. A rectangular prism (cuboid) has 6 faces—3 pairs that are the same size. The area is the total of the areas of these pairs of faces. It can be computed by ...
A = 2(LW + WH + LH)
For your rectangular prism, this is ...
A = 2((8 cm)×(6 cm) + (6 cm)×(2 cm) + (8 cm)×(2 cm))
= 2(48 sq cm + 12 sq cm + 16 sq cm)
= 2×(76 sq cm)
= 152 sq cm
Given:
r = 3.8x10⁵ km = 3.8x10⁸ m, the distance between the earth and moon,
F = 20.46x10²⁵ N, the gravitational force between the earth and the moon,
G = 6.674x10⁻¹¹ m³/(kg-s²), gravitational constant
M = 5.972x10²⁴ kg, the mass of the earth.
Let m = mass of the moon.
Then
F = (G*M*m)/r^2
or
m = (F*r^2)/(G*M)
In SI units,
m = [20.46×10²⁵ * (3.8×10⁸)²]/[6.674×10⁻¹¹ * 5.972×10²⁴]
= 7.4125×10²⁸ kg
Answer: 7.4125x10²⁸ kg
X2 - 12 = y, where x=the number of hours since 7 am, and y=the water level
Supplementary angles are two angles whose sum is 180 degrees while complementary angles are two angles whose sum is 90 degrees. Supplementary and complementary angles do not have to be adjacent (sharing a vertex and side, or next to), but they can be. ... The difference is their sum.
